Identify the correct statement about the cell wall: MCQ with Answer and Explanation

Explanation:
Under normal conditions, the brain relies almost exclusively on glucose for energy. During prolonged fasting, it can adapt to use ketone bodies. Fatty acids cannot cross the blood-brain barrier.

Explanation:
Restriction enzymes recognize specific palindromic sequences and cleave the DNA backbone, producing sticky or blunt ends for cloning.

Explanation:
The cell wall is porous and does not regulate entry; the plasma membrane is selectively permeable. Thus, the wall is freely permeable, and the reason explains it.